I tried, mostly just for my own amusement, to again align the SHG. The reflected beam overlaps the incident and I brought the power to a reasonable level by beam walking the two steering mirrors just before the cavity, but still no clear mode structure. I guess due to the temperature the z-direction mode matching is not good enough - the beam waist inside the nonlinear crystal cavities is very small and extremely sensitive to tuning. So I guess we just wait for the air conditioning to be fixed.

I replaced a faulty 3x2 power plug board that was making an uncomfortable crackling noise with a 6x1 board. The connected items are the homodyne power supply, power meter power supply and one other item.